1. Field of the Invention
This invention relates to cased telescoped ammunition, and more particularly to an improved ammunition of this type which is inexpensive to manufacture, accommodates the use of high energy main propellants, and provides control of main propellant ignition.
2. Description of the Prior Art
A typical design for cased telescoped ammunition is shown in FIG. 1. It comprises a cylindrical rolled steel casing 10 enclosing a bullet 14. A control tube 16 extends aft from roughly the midpoint of the casing 10. A granular propellant 18 is housed in the control tube 16 and upon initial ignition forces the bullet out of the casing. The control tube 16 includes a recess 20 into which fits a primer. A metering tube 22 is disposed from roughly the midpoint of the casing, forward, leaving an angular gap 24 through which propellant 18 ignites a solid main propellant 26 which surrounds the control and metering tubes. A base seal 28 and a front seal 30 secure the case to the metering tube and the control tube, respectively. In operation, the primer ignites the propellant 18 in the control tube which causes the bullet 14 to move forward. As the bullet moves forward, the expanding gas from propellant 18 ignites the main propellant 26 through the gap 24 between the control tube and the metering tube.
While generally satisfactory, cased telescoped ammunition of the type just described requires a solid molded main propellant in order to prevent the propellant from entering the cavity through which the bullet passes. Forming the solid propellant is a labor intensive and costly process. Further the use of molded solid propellants prevents the use of certain desirable high-energy propellants which cannot be readily molded.